Riding lawn mower



FIG. 1 is a perspective view of a riding lawn mower embodying the design of the present invention.

FIG. 2 is an front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof. 

The ornamental design for a riding lawn mower, as shown and described. 